Octa-chloro-biphenyl quinone



Patented Sept. 14, 1948 e Sr:

2,449,088 OGTA-GHLORO-BIPHENYL QUINONE- Frankli-ii D'. Smitli,-.Wbster Grovcs,"Mo., assignor' to"Monsa1itoChem ical Company,'St'. Louis, Mo.,

No-Drawing'e Application July 23, 1945, Serial'No. 606,723

This invention relates to dihydroxy' octa' chlorobiphenyl and octa-chlorobiphenyl quinone and to a process forproducir g-same.

The principal object ofth e invention is-to-pro-- vide a commercially feasible process by wliich the above new compounds may-be-producedina practically pure formand in substantially quan titative yields.

Other objects of theinventionwiH be apparentto those skilled in the art as the descriptionproe One method consists in preparing. dihyd'roxyli octa-chlorobiphenyl in the above described man ner and then converting this compound-intothe corresponding quinone by oxidation The second method-"involves reacting...decachlorobiphenyl with an alcoholic solution ofanalkaline compound to introducefat leas't two hydroxyl groups and. then oxidizingith'e result;- ing chlcrohydroxy'compoundby means of acombined oxidizing and chlorihatingagentT This is preferably accomplished by' reactingfd'ca chlorobiphenyl with alcoholic OHQpreferaBIy'I a methanol solution of K'O'HI. to form a chlorohydroxy compound and then oxidizing the: lat ter by-means of aqua regia' or' an equivalent 'ox'i diz'ing agent." This is the preferredmethodb-' cause it does not require thattlde deca-chl'oro biphenyl and the alcoholic potassiu'mvhydroxide be accurately proportioned-so as to Jyield'the. dihydroxy derivative. Thus if more tli'an 'itwb chlorine atoms of deca-chlorobiphenyl are rel placed by hydroxylfgroups; oxidationof'the-ifi termediate still yields? the desired; product" since all but' two hydroxyl tg'roups' (whicliiare con; verted to oxo groups) are replacedfby chlorine through the chlorinatingaction ofthefoxidi'ziii'g; agent. g

Dihydroxy octa-chlorobiphenyh and octadroxyocta-chloroblphenyl finds'use as" a gemcideand" octa-chlorobiphenyl quinoneis. adapt ed for use as an insecticide; a fungicide, aherb'iT- cide; a fireproofing compound, a stabilizer for dielectric compositions, an oil additionagent'g a pigment for-plastics, paints, varnishes and lacquers, and as an intermediate in theproductio'ni of dyestuffs.

The above hydroquinone (dihydroifyToc'tachlorobiphenyl) and the corresponding qui'non'e (octa-chlorobiphenyl quinone) may be represented generically by the followingtstructurall formulae 01 e1 c1 01 wherein both X and Y are selected from the class consisting of 0x0 and hydroxyl groups, it being understood that the' unsaturated bonds (not showni occupydifierent positions in -tlie' for?" mula depending upon the substituents xeand 'yr Thus' when X and Y are 'both ioxo groupsi the" above formula takes the followingform':

On theother hand; when Xaridl Y are both; h'y-l' droxyl groups, the double bonds occupy .difireiiti positionsand the structural. formula isfthn r'ep resented as follows:

cic1 01: 5 a

For a more complete understanding of the present invention, reference is made to the following sp'eciflc examples it being :understood that these embodiments are" merelyillustrative and are in no way, .limitative of the scope-of the invention:

Example? gramsof deca-chlorobiphenyl,--- i2 -grams-of KOI-I and 250- cc. of ethylene-glycol weresmixedtogether; and refluxed for8 -hours.- Thesolution thus obtained was-diluted with waterto a-vole 0 umeofl liter and an'excess otKdHwas added chlorobiphenyl quinone may .be employed for a. I

great varietyof purposes: For example; dihy to forma clear solution which-Was filtered-rand. acidified with I-I Cl, consisting essentially of dihydroxy octa-chloro biphenyl wasfiltered,- -dried in a vacuum-oven and ground to a white=crystallinepowder.

The precipitated product Example II 50 grams of deca-chlorobiphenyl, grams of KOH and 250 cc. of ethylene glycol were mixed together and refluxed for six hours. The resulting product was poured into water and after making certain that the solution was basic, it was filtered. The filtrate was then acidified with concentrated hydrochloric acid and the white chlorohydroxy product recovered by filtration.

ljhe product thus obtained was treated while stirring with an excess of aqua regia (1 volume of concentrated nitric acid to 4 volumes of con centrated hydrochloric acid). The reaction mixture was thereupon heated slowly to C. and as the reaction progressed the white crystalline hydroxy derivative was converted into an orange colored solid. At the end of six hours, the reaction mixture was allowed to stand overnight whereupon it was poured into Water and filtered. The filter cake consisting of octa-chlorobiphenyl quinone was then washed with water and dried at room temperature.

Example IV 500 grams of deca-chlorobiphenyl, 250 grams of KOH, 1500 cc. of ethylene glycol and 2 cc. of water were mixed together and refluxed with stirring for a period of eight hours. The resulting product was poured into 2 liters of water and after making certain that the solution was basic, it was filtered. The filtrate was acidified with concentrated hydrochloric acid and the precipitate produced was filtered and washed with cold water. The moist precipitate was allowed to stand overnight and then it was heated in a beaker with 2500 cc. of aqua regia to convert the chlorohydroxy derivative into octa-chlorobiphenyl quinone. This product was soluble in methanol and ethanol and on analysis was found to contain 60.19% chlorine as compared with 61.6% C1, the theoretical chlorine content of octachlorobiphenyl quinone.

Example V 100'grams of deca-chlorobiphenyl, 500 cc. of ethylene glycol, 50 grams of KOH and 2 cc. of water were refluxed for eight hours and then the resulting solution was filtered to remove a small amount of undissolved solid material. After dilution with 1300 cc. of cold water, the filtrate was filtered, using Filter-Gel, and then acidified with an excess of concentrated hydrochloric acid. This resulted in the production of a hard, lump; brownish precipitate which, upon reaction with 500 cc. of aqua regia (4HClzlI-1N0a), yielded an orange colored crystalline product. The reaction mixture, after standing overnight, was diluted with water to a volume of two liters and filtered. The filter cake was then dried overnight at a temperature of about '75 to 80 C. and ground to a powder in a mortar. 86 grams of octa-chlorobi- 4 phenyl qninone was obtained, a product yield of 93.5% of theory.

Example VI 2000 grams of deca-chlorobiphenyl, 10 liters of ethylene glycol, 1000 grams of KOH and 35 cc. of

water were mixed together and refluxed in a 12 liter flask for 8 hours. At the end of this period, the reaction mixture was filtered through a bed of Filter-Gel, using glass filter cloth, and then acidified with concentrated hydrochloric acid. The chlorohydroxy compound precipitated as a result of acidification was separated from the solution by filtration and reacted with a mixture of 5 liters of concentrated HCl and 1 liter of concentrated nitric acid. The reaction mixture was then allowed to stand at room temperature for 36 hours and after dilution with water, it was illtered. The filter cake consisting of octa-chlorobiphenyl quinone was washed with water and dried in an oven for 24 hours at a temperature of 80 C.

In converting deca-chlorobiphenyl into dihydroxy octa-chlorobiphenyl, I employ an alcoholic solution containing a. sufficient amount of an alkaline compound to supply two hydroxyl groups per mole of the chlorinated compound, but a slight excess (up to about a 10% molar excess) of the alkaline compound is preferred since this insures the formation of a product consisting essentially of the dihydroxy derivative.

When octa-chlorobiphenyl quinone is the desired end product and the intermediate is to be converted by means of an oxidizing agent which has no chlorinating action, it is essential that the deca-chlorobiphenyl and the alkaline compound be accurately proportioned so as to form dihydroxy octa-chlorobiphenyl, otherwise oxidation of the intermediate will not yield octa-chlorobiphenyl quinone. However, if a combined oxidizing and chlorinating compound such as aqua regia is employed, then an accurate adjustment of the above reactants is not necessary provided the alkaline compound is used in an amount sufficient to replace at least two chlorine atoms of deca-chlorobiphenyl by hydroxyl groups.

When .more than two chlorine atoms of decachlorobiphenyl are substituted by hydroxyl groups through the use of a large excess of the alkaline compound, oxidation by means of aqua regia or its equivalent still yields octa-chlorobiphenyl quinone. hydroxyl groups in the para positions are oxidized by aqua regia to the corresponding oxo groups whereas the remaining hydroxyl groups are substituted by chlorine atoms through the chlorinating action of the aqua regia.

In general, I employ from 2 to 4.5 moles of the alkaline compound per mole of deca-chlorobiphenyl, but it is to be understood that a larger molar excess of the former compound is within the scope of the present invention.

After the reaction between deca-chlorobiphenyl and the alkaline compound has gone to completion, the reaction mixture, if it is not already in this condition, is rendered basic by the addition of a, suitable alkali. The basic solution is thereupon filtered to remove solid impurities and then acidified, preferably by means of con-- 1 centrated hydrochloric acid, in order to precipitate" the chlorohydroxy compound. This compound is then oxidized by means of aqua-regia to form octa-chlorobiphenyl quinone. In this reaction the quantity'of oxidizing agent may be varied widely so long as the theoretical require-. ments are met, but I prefer to employ an excess The reason for this is that the.

of this material. The degree of excess depends to a large extent on the quantity of alkaline compound employed in the initial step of the process. If a. large excess of alkaline compound is employed in this reaction and more than two chlorine atoms of deca-chlorobiphenyl are replaced by hydroxyl groups, then a large excess of aqua regia must be used. On the other hand if only a slight excess of the alkaline compound is employed, then the amount of aqua regia used may approach more closely the theoretical requirements.

In addition to aqua regia, other oxidizing agents such as nitric acid, KC'lQs in concentrated H01, K2CI'2O7 in HCl, etc. may be used. The only limitation on the oxidizing agent is that it must be eifective in acid solution.

The optimum oxidation temperature varies with the reagent but when aqua regia is employed I prefer to carry out this reaction at about 35 C.

The temperature used to dry dihydroxy octachlorobiphenyl and octa-chlorobiphenyl quinone is not critical. It may vary from room temperature up to 80 C. depending upon the rapidity with which it is desired to dry the product. Much higher temperatures may also be utilized so long as those temperatures producing substantial decomposition are avoided.

Where reference is made to an alkaline com- FRANKLIN D. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,995,568 Jacobi Mar. 25, 1935 2,353,724 Gump July 18, 1944 OTHER REFERENCES Karrer, (Organic Chemistry, page 531. Richters Organic Chemistry, vol. II, translated by DAlbe, pages 557-558. 

